$breakpoints: (
  'default': 0,
  'xs': 320px,
  's': 480px,
  'm': 768px,
  'l': 1024px,
  'xl': 1280px,
  '2xl': 1536px,
  'nav': 1000px,
) !default;

@mixin breakpoint($breakpoint) {
  @if map-has-key($breakpoints, $breakpoint) {
    @media (min-width: map-get($breakpoints, $breakpoint)) {
      @content;
    }
  } @else if (type_of($breakpoint) == number) {
    @media (min-width: #{$breakpoint}px) {
      @content;
    }
  } @else {
    @error "Not a correct value";
  }
}
